Fate/stay night UNLIMITED BLADE WORKS

In the World before, novice mage Shirou Emiya summoned and bonded with beautiful heroic spirit Saber as they became enmeshed in the battle for supremacy known as the fifth Holy Grail War. Fate, however, is a fickle mistress, and there was more than one way for that story to transpire. Now, in an alternate timeline, the pairing’s destiny becomes more tightly intertwined with that of high school student/secret Mage Rin Tohsaka and her Servant Archer. Even if you think you know what will happen next, prepare to be surprised as new twists await at every turn.